PLANTATION KEY -- In the coming months, a 32-inch pipeline is expected to be drilled 40 feet under Tavernier Creek as part of an ongoing construction project connecting Islamorada residents to Key Largo's sewage treatment plant.

The pipe will need to be 1,500 feet long to cross under the creek, says Richard Crow, project manager for Layne Construction, which is overseeing the effort for the village of Islamorada.

The pipe will slope 40 feet under the creek's bed to avoid other utilities and because that's the safest place for the pipe.

"We want to go as low as we can go," says Kevin Pope of Underground Utilities Solutions, which is negotiating to get the project.

Crow acknowledges that the pipe will be carrying sewage but says the contents have little impact on how the pipeling is constructed. Crow, who worked on parts of the Key Largo wastewater project, said his company ran a pipe along the bridge at the Marvin D. Adams Waterway, known commonly as "the cut," rather than going under it.

Running the pipe underground has concerned some Key Largo Wastewater Board members, who question what would happen if something went wrong with the pipe 40 feet below.

But Crow said he would like to offer some comfort.

"Going underground is the safest way to do it," Crow said. "And it's not a decision just made by Layne."

Many projects on the mainland follow the same guidelines, and running pipes under waterways is approved by state inspectors, he said.

"[The inspectors] don't just come by at the end when we're done, and say, 'Good job,'" he said.

As required by law, an independent scientist will be on hand to monitor the project.

"If we see any manatees, we shut down until they leave the area," Pope said as an example of some of the precautions they take.

Both Pope and Crow said safety is the top priority.

"It's not just a word with us," Crow said.

Three tanks will recycle mud pulled from under the bed as the line is being installed. Construction is to begin on the south side of the bridge,

Drilling into coral rock, Pope and Crow say, is easier than drilling into mud and sand on the mainland.

The project may have an impact for a few weeks on local businesses on the southwest side of the bridge along Freeland Road.

"Any impact is a bad day," Crow said.

The Tavernier Creek extension is just one of many underground pipelines expected to be built in Islamorada. Others will run under Snake Creek, Whale Harbor and the Tea Table-Indian Key fill bridges.